Primary Partition lost

Hi everyone,
I have a 500GB HDD divided in to 55.5GB Primary boot partition (C: ) with Win7 and Programs and remaining space ~410GB partitioned (D: ) is where my data is stored.
Somehow my kid touched something, somewhat... and my PC won't boot. When I boot Linux from my USB dongle i see that partition C: has unknown file system, Used/Unused space unknown and it is not mounted. The other partition has the data intact and it is accessible.

I still have some documents on My Documents (C: ) that I need to retrieve. Is there any way to fix this partition so I can retrieve this data on lost partition without risking the remaining data on the other, healthy partition.

Thank you in advance!

Dear Golden,
Problem is that I can't access my partition at all. Gparted shows this partition as unknown file system with -- used and -- unused space.
I need some sort of tool to repair this partition or retrieve data. I Tried MiniTool Partition Wizard Bootable, but the iso file is not creating Bootable disk/USB.

Yes. Use Rufus to create a bootable pen drive with pwhe811.iso. During the process if it offers to download the new vesa32 menu say yes. It will download and use the new vesa menu to create the pendrive.



Otherwise, when booting with it, against the command prompt you have to type linux0 and ENTER to boot PW. (linux1 to boot PW in safe mode, and local to boot from HDD)

The second thing, you merely said you are unable to boot your PC. If you tell what exactly happens when you try to boot, it may throw some light on what could have happened and may be there can be some alternate method to set it right.